A conventional wrench generally includes a head connected with a handle and a driving member is rotatably received in a through hole defined through the head. A recess is defined in an inner periphery of the through hole so as to receive a ratchet mechanism therein which includes a pawl controlled by a selector so as to engage with the driving member. The conventional wrench includes only limited number of function. Furthermore, the conventional wrench is made of metal boards which are heavy and several different machining steps, such as forging, heat treatment, polishing, and boring have to be taken to form the existed appearance of the conventional wrench. Each machining step requires a specific machine to complete, so that the assembling procedures can be time-consuming.
The present invention intends to provide a wrench that is easily to make and includes different functions.